You don't need to shop your idea around with other entrepreneurs to see if it's worth anything. All you have to do is go to a potential customer and ask them to pay.
By paying, they're not giving you some "feel good" critique... they're giving you concrete feedback on things they need to see in order to continue paying. Try it out - next time you have an idea ask someone for a measly $1. Even handing over that $1 is a great exercise in serious feedback.
I'm working on a side project for helping people stay motivated on their diets. Before I started writing a scratch of code, or sketching out any mockups, I got someone to pay me. I asked a potential customer to pay me $30/mo for the service my app would provide. The darndest thing happened - I was paid. And it lasted for 3 months.
The feedback I got was incredibly useful... not your typical "Yeah, good idea. You should do X. I'm sure you'll be the next Facebook."
It was: "Uh, you need to give me a meal plan or I'm giving up. You better text me at 7AM and remind me to hit the gym. You better do X and Y or else I'm done. How come you didn't text me around lunch?"
I'm now working on a slightly more ambitious concierge MVP, and reaching out to my next small batch of customers. It's exciting.
Do the same with your product/service/idea. You'll find the feedback invaluable, and it may even save you an entire year of wasted time.
